For research use only. Not for use in diagnostic procedures.
Some common signs of a bad ethernet card include:
1) The card disappears from the computer configuration. The card can no longer be seen in the device manager on a PC.
2) The card becomes corrupted after a Windows OS update.
3) A small light on the card appears (revealing a backlit 100x) when an ethernet cable is plugged in.
Poor ethernet card performance can be effected by dust inside the PC or on the cooling fan, so regular internal computer maintenance is required to remove buildup on the microprocessor. Dust buildup can also cause components to become overheated, and this would damage the ethernet card as well.
A good ethernet card connection can be pinged when testing the physical connection of the card to the instrument.